The present invention relates generally to apparatus and methods for closing and/or sealing openings through tissue, and more particularly to apparatus and methods for delivering a closure element for closing a puncture in a blood vessel or other body lumen formed during a diagnostic or therapeutic procedure.
Catheterization and interventional procedures, such as angioplasty or stenting, generally are performed by inserting a hollow needle through a patient""s skin and muscle tissue into the vascular system. A guide wire may then be passed through the needle lumen into the patient""s blood vessel accessed by the needle. The needle may be removed, and an introducer sheath may be advanced over the guide wire into the vessel, e.g., in conjunction with or subsequent to a dilator. A catheter or other device may be advanced through a lumen of the introducer sheath and over the guide wire into a position for performing a medical procedure. Thus, the introducer sheath may facilitate introduction of various devices into the vessel, while minimizing trauma to the vessel wall and/or minimizing blood loss during a procedure.
Upon completion of the procedure, the devices and introducer sheath may be removed, leaving a puncture site in the vessel wall. External pressure may be applied to the puncture site until clotting and wound sealing occur. This procedure, however, may be time consuming and expensive, requiring as much as an hour of a physician""s or nurse""s time. It is also uncomfortable for the patient, and requires that the patient remain immobilized in the operating room, catheter lab, or holding area. In addition, a risk of hematoma exists from bleeding before hemostasis occurs.
Various apparatus have been suggested for percutaneously sealing a vascular puncture by occluding the puncture site. For example, U.S. Pat. Nos. 5,192,302 and 5,222,974, issued to Kensey et al., describe the use of a biodegradable plug that may be delivered through an introducer sheath into a puncture site. When deployed, the plug may seal the vessel and provide hemostasis. Such devices, however, may be difficult to position properly with respect to the vessel, which may be particularly significant since it is generally undesirable to expose the plug material, e.g., collagen, within the bloodstream, where it may float downstream and risk causing an embolism.
Another technique has been suggested that involves percutaneously suturing the puncture site, such as that disclosed in U.S. Pat. No. 5,304,184, issued to Hathaway et al. Percutaneous suturing devices, however, may require significant skill by the user, and may be mechanically complex and expensive to manufacture.
To facilitate positioning devices that are percutaneously inserted into a blood vessel, xe2x80x9cbleed backxe2x80x9d indicators have been suggested. For example, U.S. Pat. No. 5,676,974, issued to Kensey et al., discloses a bleed back lumen intended to facilitate positioning of a biodegradable plug within a puncture site. This device, however, requires that an anchor of the plug be positioned within the vessel, and therefore, may increase the risk of over-advancement of the plug itself into the vessel.
Alternatively, U.S. Pat. No. 5,674,231, issued to Green et al., discloses a deployable loop that may be advanced through a sheath into a vessel. The loop is intended to resiliently expand to engage the inner wall of the vessel, thereby facilitating holding the sheath in a desired location with respect to the vessel. The loop may also provide a support for facilitating the deployment and deflection of a surgical clip against the vessel wall. Such a device, however, may risk engagement between the loop and the surgical clip, thereby preventing the loop from being withdrawn from the vessel.
Accordingly, apparatus and methods for delivering a device for closing a vascular puncture site or other opening through tissue would be useful.
The present invention is directed to apparatus and methods for closing and/or sealing openings through tissue, e.g., into body lumens, and more particularly to apparatus and methods for delivering a vascular closure element for closing a puncture in a blood vessel formed during a diagnostic or therapeutic procedure.
In accordance with one aspect of the present invention, an apparatus is provided for delivering a closure element or other annular-shaped device into an opening through tissue, e.g., for engaging tissue adjacent the opening to close and/or seal the opening. The apparatus generally includes an elongate member including proximal and distal ends defining a longitudinal axis therebetween, and an outer surface extending between the proximal and distal ends. In one embodiment, the elongate member may be an introducer sheath that includes a lumen for advancing one or more devices into a body lumen during a procedure.
A carrier assembly may be slidable on the elongate member from the proximal end towards the distal end, the carrier assembly including a carrier member and a pusher member movable distally relative to the carrier member. A distal end of the pusher member may be disposed proximal to a distal end of the carrier member, e.g., if the pusher member has a substantially shorter length than the carrier member, thereby defining a space distal to the pusher member along an outer surface of the carrier member. An annular-shaped element, e.g., a clip or other closure device, may be received on the carrier member, the annular-shaped element being deployable from the carrier member upon distal movement of the pusher member relative to the carrier member.
Optionally, the carrier member may include one or more ramped portions, each portion defining a ramped distal surface and/or a ramped proximal surface. The closure element may include a plurality of tines extending distally, the tines being disposed proximal to the one or more ramped portions such that the ramped portions may protect the tines during advancement of the carrier assembly. In addition, the pusher member may advance the closure element over the one or more ramped portions when the carrier assembly is advanced to a distal position, e.g., for directing the tines radially outwardly to engage surrounding tissue.
A skin overlies at least a portion of the outer surface of the elongate member and the carrier assembly, the skin being separable from the outer surface of the elongate member as the carrier assembly is advanced from the proximal end towards the distal end of the elongate member. In one embodiment, the skin may include a weakened region, e.g., a thin and/or perforated region, extending axially along the skin. The weakened region may be configured to tear preferentially as the carrier assembly is advanced from the proximal end towards the distal end of the elongate member. In another embodiment, the skin may include a flap extending axially along the outer surface of the elongate member and overlying an adjacent region of the skin. The flap may be bonded to the adjacent region such that the flap may be separated from the adjacent region as the carrier assembly is advanced towards the distal end of the elongate member.
In addition or alternatively, the skin may be bonded to the outer surface of the elongate member by an adhesive. The adhesive may have sufficient adhesive strength such that the skin may be peeled away from the outer surface as the carrier assembly is advanced towards the distal end of the elongate member.
The apparatus may also include an actuator assembly including a housing extending from the proximal end of the elongate member, e.g., connectable by cooperating detents, and one or more elongate actuator elements that are movable axially relative to the housing. The actuator elements may be connected to the carrier assembly for coupling movement of the carrier assembly to the one or more actuator elements. For example, the carrier assembly and the actuator elements may include cooperating detents for coupling distal movement of the carrier assembly to the one or more actuator elements as the control member is directed distally. The cooperating detents may release the carrier member upon attaining a distal position, thereby permitting further distal movement of the pusher member to deploy the closure element from the carrier member.
During use, the distal end of the elongate member may be inserted into an opening through tissue, e.g., into a puncture communicating with an artery or other blood vessel. If the elongate member is an introducer sheath, one or more instruments may be inserted through the sheath, e.g., into a blood vessel accessed via the opening. A diagnostic and/or therapeutic procedure may be performed within a patient""s body, e.g., via the blood vessel accessed via the opening. Upon completion of the procedure, any instruments may be removed from the sheath, the handle assembly may be connected to the proximal end of the elongate member, and/or an actuator may be coupled to the carrier assembly. Optionally, the distal end of the elongate member may be positioned relative to the blood vessel, e.g., using a bleedback indicator or a tactile indicator, such as an expandable obturator.
To deploy the closure element, the carrier assembly may be advanced towards the distal end of the elongate member. The carrier assembly may cause the skin to separate from the outer surface of the elongate member as the carrier assembly is advanced towards the distal end. If the skin includes a weakened region extending towards the distal end of the elongate member, the weakened region may tear preferentially as the carrier assembly is advanced towards the distal end of the elongate member. If the skin includes a flap extending axially along the outer surface of the elongate member and overlying an adjacent region of the skin, the flap may be released from the adjacent region as the carrier assembly is advanced towards the distal end of the elongate member, thereby allowing the skin to separate from the outer surface. In addition or alternatively, if the skin is bonded to the outer surface of the elongate member by an adhesive, the adhesive may have sufficient adhesive strength to release as the carrier assembly directs the skin outwardly such that the skin is separated from the outer surface as the carrier assembly is advanced towards the distal end.
As the carrier assembly is advanced, the carrier assembly may pass between the skin and the outer surface of the elongate member. Thus, if the opening through tissue extends through one or more layers of fascia or other tissue structures, the skin may facilitate advancing the carrier assembly through the layers and/or minimize the risk of the carrier assembly or the closure element catching on tissue as it is advanced towards the distal end of the elongate member.
The closure element may be deployed from the carrier assembly within the opening, e.g., by ejecting the closure element from the carrier assembly and/or by withdrawing the elongate member from the opening. With the elongate member withdrawn, the closure element may substantially close or seal the opening, e.g., to prevent blood flow therethrough, thereby allowing the opening to heal.
In accordance with another aspect of the present invention, an apparatus is provided for delivering a closure device that includes an elongate member, e.g., an introducer sheath, including proximal and distal ends defining a longitudinal axis therebetween, and an outer surface extending between the proximal and distal ends. A hub may be provided on the proximal end of the elongate member, the hub including one or more alignment tabs or spacers disposed about the periphery of the hub and/or spaced away from the outer surface of the elongate member.
A closure element, e.g., a clip, may be provided that includes a generally annular-shaped body including proximal and distal ends and a plurality of tissue engaging portions extending from the distal end. The proximal end of the closure element may be held away from the outer surface of the elongate member by the one or more spacers.
An actuator or handle assembly is provided that includes an actuator member slidable between the hub and the outer surface of the elongate member. The actuator member includes one or more elements for coupling with the closure element, whereby distal movement of the actuator member advances the closure element towards the distal end of the elongate member. In one embodiment, the hub may include an annular hub defining a passage between the annular hub and the outer surface of the elongate member, e.g., attached to the elongate member by one or more radial spokes. The actuator member may include a tubular member, e.g., defining a xe2x80x9cCxe2x80x9d shaped cross-section for inserting the tubular member through the passage around the one or more radial spokes.
In a preferred embodiment, the tubular member may include one or more protrusions or tabs, e.g., extending radially outwardly from the distal end of the tubular member. The closure element may include a plurality of pockets for receiving respective tabs on the tubular member therein, thereby coupling the closure element to the tubular member using the tabs. For example, the closure element may include a plurality of alternating diagonal elements extending between the proximal and distal ends of the closure element. The distal end of the closure element may include curved elements connecting adjacent diagonal elements, the curved elements defining the pockets.
Optionally, a skin may overlie at least a portion of the outer surface of the elongate member between the carrier assembly and the distal end of the elongate member, and may at least partially overlie the closure element. The skin may be separable from the outer surface as the closure element is advanced towards the distal end of the elongate member, similar to the previous embodiment.
During use, the distal end of the elongate member may be inserted into an opening through tissue, e.g., into a puncture communicating with a blood vessel, and a procedure may be performed, similar to the previous embodiment. Upon completing the procedure, a distal end of the actuator member may be inserted between the hub and the outer surface of the elongate member. Thus, the actuator member may pass under the spacers, and consequently, under the proximal end of the closure element, until the distal end of the actuator member is coupled with the closure element, e.g., received in pockets adjacent the distal end of the closure element. The actuator member may be advanced distally, thereby advancing the closure element towards the distal end of the elongate member. Tissue adjacent the distal end of the elongate member may be engaged with tissue engaging elements on the closure element, and the elongate member may be withdrawn from the opening, leaving the closure element to close and/or seal the opening. Alternatively, the closure element may be carried by the distal end of the actuator member, rather than being disposed initially adjacent the hub. In this alternative, the closure element may be introduced between the hub and the elongate member when the actuator member is connected to the hub, and advanced along the elongate member as the actuator member is advanced.
Other objects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.